Northern California man celebrating his 21st birthday drowns while carrying a rock across a pond

A Northern California man celebrating his 21st birthday drowned after attempting to swim across a pond while carrying a 10-pound rock, authorities said.

Austin Harr was enjoying his birthday with friends about 5:07 p.m. Monday at the Oroville Wildlife Area when he tried to carry the rock across the Gridley Plunge, one of numerous dredger ponds at the 11,800-acre state park, according to the California Highway Patrol.

The Gridley, Calif., resident suddenly disappeared under the water. After several minutes passed and Harr had still had not emerged, his friends tried searching for him, and then called for help.

Nearly an hour later, rescue workers found Harr and pulled him from the water to perform CPR. He was taken to an area hospital, where he was pronounced dead.

The CHP and the Butte County sheriff coroner’s office are investigating Harr’s death. CHP officials said they believe alcohol played a role in his death.